Bending machine wiper die supporting means



Sept. 29, 1959 s. e. GERL ACH BENDING MACHINE WIPER DIE SUPPORTING MEANSFiled Aug. 13, 1957 2 Sheets-Sheet 1 i WM,

Jim I Sept. 29, 1959 s. G. GERLACH 2,906,316

BENDING MACHINE WIPER DIE SUPPORTING MEANS Filed Aug. 13, 1957 2Sheets-Sheet 2 INVENTOR.

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United States Patent BENDING MACHINE WIPER DIE SUPPORTING MEANS StephenG. Gerlach, Burbank, Calif.

Application August 13, 1957, Serial No. 677,869

Claims. (Cl. 153-40) This invention relates to machines for bendingtubes and bars, commonly referred to astube bending machines, and moreparticularly to an adjustable mounting means for the wiper die componentof the workpiece engaging elements of the machine. Machines of the abovecharacter employ different sets of dies for each diameter of tubing orbar to be bent therein and for each radius of bend in each size andcross sectional shape of the workpiece. These elements comprise aforming die mounted for rotation or oscillation and having a workpieceengaging surface engaging half of the perimeter of the workpiece andcurved about the radius of the inner dimension of the bend to be formedand also including a straight portion disposed'tangentially to thecurved portion and similarly shaped to engage the perimeter of theworkpiece, a clamping die associated with the forming die and movabletoward and away from the straight portion of the forming die to clampand release the end of the workpiece beyond the point of the bend, aguiding die engaging the opposite portion of the perimeter of theworkpiece and extending from a plane normal to the axis of the workpieceand intersecting the axis of rotation of the forming die toward theopposite end of the workpiece, and awiper die disposed on the oppositeside of the workpiece from the guiding die and engaging the same half.of the workpiece perimeter as the forming die on one face thereof andon the opposite face thereof being shaped to closely-fit theworkengaging curved surface of the forming die so shaped that when inalignment with the forming die the workpiece engaging surface thereof'is disposed tangentially to the said curved surface of the forming die.In use, the guiding die and wiper die grip the workpiece sufficiently tohold the movement thereof in a straight line as the Work is pulledbetween them incident to rotation or oscillation of the forming die inmaking a bend. To make accurate bends, particularly in thin walledtubing, it is essential that the wiper die be extremely accuratelypositioned with respect to the forming die. As before stated each sizeof material to be bent and each radius of bend requires a separate setof these dies; At each set-up, the wiper die of a given set of dies mustbe accurately adjusted and heretofore such adjustment has been a matterof trial and error on each set up of the machine, such set-ups sometimesconsuming hours.

With this problem in mind, the principal object of the invention is toprovide a mounting means for the wiper dies of die sets used in bendingmachines which is adjustable vertically, horizontally laterally of theaxis of the endwise movement of the workpiece, and rotatively about avertical axis disposed at the work advancing side of the forming dieaxis.

Another object of the invention is to provide an adjustable mountingmeans for the wiper die of a bending machine die set which is adjustableas' above stated and which includes indicia means whereby the correctsetting for each wiper die as initially determined by trial and errormay be noted and recorded with resultant elimina- '2 is engaged by a pin20 extending transversely of the tion of time in trial and error settingwhen the specific set of dies including the wiper die is again used.

With the foregoing objects in view, together with such additionalobjects and advantages as may subsequently appear, the invention residesin the parts, and in the construction, combination and arrangement ofparts described, by way of example, in the following specification of apresently preferred embodiment of the invention, reference being had tothe accompanying drawings which form a part of said specification and inwhich drawings:

Fig. l is a fragmentary top plan view of a bending machine showing thewiper die mounting means of the present invention mounted thereon,

Fig. 2 is a front elevation view, a portion of the wiper" die beingbroken away to conserve space,

Fig. 3 is a sectional plan view taken on the line 3-3' of Fig. 2,

Fig. 4 is a fragmentary side elevational view of the right hand side ofFig. 2,

Fig. 5 is a medial sectional view taken on the lines 5-5 of Fig. 1,

Fig. 6 is a plan sectional view taken on the line 66 of Fig. 4, and

Fig. 7 is a sectional view taken on the line 7-7 of Fig. 5.

Referring to the drawings, the device is shown applied to a bendingmachine comprising a bed or frame member A on which a forming die B anda cooperating clamp member C are mounted for movement about an axis D.

A guiding die E is fixedly mounted on the bed A forengagement with theside of the workpiece comprising a lel bearing surfaces H provided witha series of spaced holes I to which the base plate 1 of the presentinvention is secured by bolts 2 in any selected position deter.- minedby the holes I.

The base 1 is a flat metal plate having a hole '3 in the center thereofin which the pilot plug 4 of the upwardly extending bracket 5 closelyfits with only suflicient clearance to permit it to be turned thereinwithout appreciable play. The bracket 5 includes a generally circularbottom portion 6 which rests on the top surface of the base 1, saidbottom portion being provided with a series of radially spaced arcuateslots 7 generated about the axis of the pilot plug 4 and through whichbolts 8 extend for threaded engagement with the base. plate l to securethe bracket 5 in rotative adjusted position. The top surface of the base1 adjacent to the side of the bottom portion 6 of the bracket 5 isprovided with graduations 9 extending on opposite sides of a centralzero position and the bottom portion is provided with an index mark 10movable along the graduations incident to the rotativeadjustment of thebracket 5 and from which the setting can be ascertained. i Y

At its upper end, the bracket carries means for adjustably supporting alaterally extending bracket armll lying generally parallel to thedirection of travel ofthe workpiece and to which the wiping die I issecured bybolts 12, and other end of said arm being formed asan integralportion of a head 13 mounted for limited move-- arms of the yoke membercarrya vertical stud element 17 having a threaded upper end 18 engagingthe upper arm 14 and a smooth lower end journaled in the arm 15. Betweenthe arms Hand 15 the stud extends through the head 13, and at the midlength of the hole in the head 13, the stud is provided with aperipheral groove 19 which head. Thus, as the stud 17 is rotated movingit upwardly or downwardly in the arms 14 and 15, the head 13 will beraised or lowered with it, the pin and groove engagement describedallowing rotative movement of the stud and limited oscillatory movementof the head while'preventing relative endwise movement between the studand head.

The upper end of the bracket is provided with a guiding and supportingmeans for the yoke 16' comprising. a side wall 21 and a rear wall 22formed integrally with the bracket 5, anda side plate 23 secured to thefree edge of the rear wall by screws 24 and extending forwardlytherefrom parallel to the side wall and engaging the side thereofopposite the side wall 21; said side plate having a shallow recess 25formed in the yoke engaging face thereof thereby holding the yokeagainst vertical. movement. A bolt 26 extending through the lowerforward edge of the side plate 23 and threadedly engaging thecorresponding portion of the side wall 21 serves to hold the plate 23 inparallelism with the side wall 21. The rear wall 22 is provided with athreaded bore 27 disposed at about the center of the rear face of theyoke 16 and the back of the yoke is provided with a bore 28 of lesserdiameter than and in axial alignment with the bore 27. A threaded stud29 is mounted in the bore 27 carrying an end portion 30 disposed in thebore 28 having a peripheral groove 31 thereon engaged by a cross pin 32disposed in a transverse bore 33 in the yoke member 16. Rotation of thestud 29 will thus move the yoke 16 and the devices carried therebyforwardly and rearwardly in a line normal to the workpiece engagingsurface of the wiper die. Preferably, the side wall 21 and the sideplate 23 are provided with bores 33 and 34, respectively, disposedopposite of and being of larger diameter than the bore 33 whereby accessmay be had to the pin 32 for removing and replacing it incident tomaintenance of the device.

The adjusting means above described are effective to allow the bracketto be adjusted rotatively about the axis of the pilot plug 4, the yoketo be moved forwardly and rearwardly in a horizontal plane and the head13 with the integrally formed bracket arm 11 which directly supports thewiper die to be adjusted vertically relative to the yoke. All of theseadjustments allow the end of the wiper die which contacts the formingdie surface to be exactly adjusted so that the workpiece engagingsurface of the wiper die extends exactly tangentially to the curve ofthe forming die workpiece engaging surface and so that the rear orforming die engaging surface of 'the wiper die fits the form die surfacewith equal exactitude, both of such engagements being necessary toaccurate bending operations.

The formation of this rear surface of wiper dies is diflicult andexacting and generally, even with seemingly identical dies, slightlydifferent settings are required for. each to operate properly. To thisend, in addition to the graduations 9 which indicate the-rotativeposition of the bracket 5, means is provided for indicating the verticalposition of the head 13 and for the horizontal position of the .yoke.Thus, once a wiper die has been satisfactorily adjusted, the dataobtained from the various means and stamped on the forming die orotherwise recorded. Thus, when the dies are again used together, thewiper die can be adjusted according to the data on the forming die withconsequent saving of both time and material in setting up the bendingmachine.

The vertical position indicating means comprises a bell crank lever 35disposed in a slot 36 extending downwardly from the upper surface of theyoke 16 and pivoted on a cross pin 37. The lever has one arm 38extending forwardly beyond the front face of the back member of the yokeand engaging a horizontal slot 39 formed in the rear face of the'head13. The lever includes a second arm 40 extending above the upper surfaceof the yoke 13 and terminating in a sharp edged pointer portion movablealong a graduated scale 41 formed on a top plate 42 secured by screws 43and extending across the top of the rear portion of the yoke 16 andhaving a slot in registry with the slot 36. Thus as the head 13 israised or lowered by the screw 17, the pointer portion of the lever arm40 will move along the scale and indicate the position of the head 13above or below a zero point at the middle of the scale, the scalepreferably indicating the position in thousandths of an inch plus orminus from the said zero position.

The top plate is further provided with a rearwardly extending tongueportion 44 slidable in a slot 45 formed in the top edge of the rear wall22 and said tongue is provided with a reference mark 46 movable past aset of graduations 47 carried by the top face of the rear wall adjacentto the slot 45; said graduations extending to either side of a centerzero mark whereby the forward or rearward position of the yoke may beobserved and recorded together with the data obtained from the otherposition indicating means.

Although the recording of the data thus obtained from an initial setupis preferably recorded on the forming die, it may, of course, bepreserved in any other manner deemed suitable. The advantage of thedevice is first that it permits the wiper die to be adjusted by preciseincrements and second, once the correct setting has been achieved, thesettings may be recorded for use in subsequent setups of the sameforming and wiper dies.

While the foregoing specification discloses by way of example apresently preferred embodiment of the invention, the invention is not tobe deemed to be limited to the exact details thus disclosed, and it willbe understood that the invention embraces all such modifications andchanges in the parts, and in the construction, combination andarrangement of parts as shall come within the purview of the appendedclaims.

I claim:

1. In a supporting means for the wiper die component of a tube and barbending machine, a horizontally extending bracket arm adapted for theattachment of a wiper die thereto, and adjustable means for supportingsaid bracket arm, said means including means for adjusting said bracketarm vertically, other means for adjusting said bracket arm horizontallytoward and away from the path of travel of a workpiece past a wiper diemounted on said bracket arm, and separate means for adjusting saidbracket arm rotatively about a vertical axis.

2. A wiper die supporting means as claimed in claim 1 in which saidmeans for adjusting said bracket arm vertically is carried by the meansfor adjusting said bracket arm horizontally.

3. A wiper die supporting means as claimed in claim 1 in which saidmeans for adjusting said bracket arm about a vertical axis carries bothof said means for adjusting said bracket arm vertically andhorizontally.

4. A wiper die supporting means as claimed in claim 1 in which each ofsaid adjusting means includes a graduated scale and a reference line onadjacent relatively movable parts by which the extent of adjustment ofeach of said adjusting means can be ascertained.

5. A wiper die supporting means as claimed in claim 1 in which saidvertical adjusting means includes means allowing limited oscillatorymovement of said bracket arm about a vertical axis.

6. In a supporting means for the wiper die component of a tube and barbending machine, a base, a bracket mounted on said base with capacityfor adjustment about a vertical axis, a horizontally extending bracketarm mounted on said bracket having means affording attachment of a wiperdie on said arm, and devices carried by said bracket and supporting saidbracket arm including devices operable to adjust said bracket armvertically and other devices operable to adjust said bracket armhorizontally in a direction normal to the workpiece engaging surface ofthe wiper die.

7. A wiper die supporting means as claimed in claim 6 in which saidmeans for adjusting said bracket arm horizontally includes a yokemounted for sliding movement on said bracket and screw threaded meansextending between said yoke and said bracket operable to move said yokerelatively to said bracket in a horizontal line extending normal to theworkpiece engaging surface of the wiper die.

8. A wiper die supporting means as claimed in claim 7 in which saidbracket arm is vertically adjustably carried by said yoke.

9. A wiper die supporting means as claimed in claim 7 in which saidbracket arm includes a head portion disposed between the arms of saidyoke and in which a vertically disposed stud extends between said armsand through said head portion and threadedly engages one of said armsand slidingly and rotatively engages the other of said arms, said studbeing freely rotatable in said head portion and being secured againstrelative endwise movement therein.

10. A wiper die supporting means as claimed in claim 9 in which saidyoke carries a bell crank lever means having References Cited in thefile of this patent UNITED STATES PATENTS 356,709 Cross Jan. 25, 1887878,604 Brinkman Feb. 11, 1908 1,024,254 Garrett Apr. 23, 1912 1,135,875Brinkman Apr. 13, 1915 1,251,678 McIntyre a Jan. 1, 1918 2,455,138Perkins Nov. 30, 1948 FOREIGN PATENTS 446,833 Germany July 12, 1927 r507,220 Germany Sept. 30, 1930 OTHER REFERENCES An article entitledProduction Tools Bend Tubing Quickly, by H. M. Williams, reprinted fromthe American Machinist of July 24, 1950.

